After ovulation, the follicle that released the egg turns into the corpus luteum. For the next two weeks, the luteal phase, it produces large amounts of progesterone. Body temperature rises by a few tenths of a degree and the lining of the uterus thickens. Without fertilisation, hormones drop and your period starts. It is in this second half of the cycle, and especially its last few days, that many women start wanting chocolate, cake or sweets.
The craving follows the hormonal calendar. It rests on measurable changes in energy use, appetite and brain chemistry, which research has been describing for almost forty years.
Your body burns a little more after ovulation
In 1986, a researcher, Paul Webb, had ten women live in a calorimetry chamber, a sealed room that measures all the energy you burn, for 36 to 46 hours at a time, at different points of the cycle (Webb, 1986). Eight of them burned 8 to 16% more energy during the luteal phase. One of them, also measured during a month on the pill, showed no increase at all that month. The author puts the extra expenditure down to progesterone from the corpus luteum.
Later studies found a smaller effect. A meta-analysis of 26 studies and 318 women confirms a small rise in resting metabolism in the luteal phase, less clear in work published since 2000 (Benton et al., 2020). So your body does burn a little more during those two weeks. The gap is modest and varies from one woman to another.
Progesterone turns up your appetite
Sex hormones play a direct part in setting hunger. Oestrogen holds food intake back, while progesterone tends to stimulate it (Hirschberg, 2012). Around ovulation, oestrogen is at its highest. After that, progesterone takes over, then both hormones fall in the days before your period.
A 2025 meta-analysis pooled 15 datasets, 330 women aged 18 to 45 with a normal weight. In the luteal phase, they ate on average 168 more calories a day than in the follicular phase (Tucker et al., 2025). The authors point out that methods vary a lot between studies, but the overall result clearly points to a bigger appetite in the luteal phase. A New Zealand review places the lowest intake just before and during ovulation (Rogan and Black, 2023).
Why sugar in particular
In the American BioCycle study, 259 healthy women were followed for one or two cycles, with records of what they ate and questionnaires on their cravings at four points in the month (Gorczyca et al., 2016). In the late luteal phase, appetite, chocolate cravings, sweet cravings in general and even salt cravings rose clearly compared with the rest of the cycle. In the mid-luteal phase, the same women also ate more protein, mostly from animal sources.
Serotonin is the most studied lead. This brain messenger affects mood, calm and fullness. In women with premenstrual syndrome, it seems to work less well by some measures, and a drop in serotonin is enough to bring on symptoms close to the syndrome. Progesterone by-products act at the same time on GABA, the system that calms nerve activity (Rapkin and Akopians, 2012).
Carbohydrates increase serotonin production in the brain. In 1989, a team at MIT admitted 19 women with severe premenstrual syndrome and 9 women without it to hospital, and measured everything they ate (Wurtman et al., 1989). At the end of the cycle, the women with the syndrome went from about 1,900 to 2,400 calories a day, with 43% more carbohydrate eaten as snacks. A carbohydrate-rich, low-protein evening meal improved their mood, tension and fatigue. The effect only appeared in the luteal phase, and never in women without the syndrome. The authors see it as a form of self-medication, with sugar used to lift low serotonin.
The study is small, old, and looks at severe cases. It still sheds light on a craving that many women know in a milder form.
A craving that says nothing about willpower
Hormones do not explain everything. A team at the University of Pennsylvania compared chocolate cravings in former students of the same university, before and after menopause (Hormes and Rozin, 2009). If hormones explained it all, the number of women affected should have dropped by 38% after menopause. It dropped by only 13%. For chocolate, other factors, such as stress, also play a part.
The two readings fit together. Your body burns a little more, progesterone drives appetite, serotonin steers you towards sugar, and stress amplifies the signal. None of this comes from a lack of character. A woman who gives in on the same days every month is responding to a physical signal. Fighting that signal head on usually ends the same way, with hunger winning, the slip, then the guilt.
What to take from it
The BioCycle women naturally ate more protein in the luteal phase, as if the body were asking for it at that point. A breakfast with 30 g of protein, a core rule at Totem, makes full sense here. Planning ahead for these days rather than putting up with them changes a lot, and how to do it depends on each woman, her cycle and her training.
The rest of the picture matters just as much. Too little sleep raises the hunger hormone and the pull towards carbohydrate-rich foods, and cortisol that stays high also pushes towards sugar. Before your period, these effects add to those of your hormones. Noticing when in your cycle the craving comes back lets you see it coming, and stop living it as a failure.
This article is for information only and does not replace medical advice.